Safety device



Dem "28,1937. w. H. WINEMAN 0 2,103,962

SAFETY DEVICE Filed May 8, 1936 .2 ,SheetsSheet l H 35 40 I I 7 4g. l NVENrozz.

- 36 41 1 2 BY A; A M,

31 33 48 a 3" ATTORNEY.

I vPatenteds'sm rr DEVICE wade flawinemapiimichizan City, Ind.,

or-to S ulliviifMachinery C mm, a comration-o! Massachusetts i l s pncaumm s, 1936, Serial No. racer v 5ic1ums. /(oll 121-=130) a g mechanism stick open. It is also desirable to tor pressure fluid conductingmeans' From certain oi. its aspects,-and in certain embodiments 5 thereof, it relates to pumping mechanism, and

more particularly to automatic shut-oil valves for use in connection with oil well pumping appai'atlis. 7 1

In connection with various fluid operated dem'vices it is desirable, and, for economy, necessary,

that "automatic supply line control'devices be pro- ,vided in order to shut ofl fluid fl owin the event oi derangement or breakage or the devices sup- 1 plied with pressure, so that the pressure supplied 18. may not blow through the devices without control 1 and result in burns orpossible injury, if the fluid to be controlled is or a dangerous nature, and

loss inany event.- I

Oil well "pumping systemsin which a central fluid for a number of expansible, chamber pumping motors, particularly when such motors are of. the fluid-operated valve type, aflord a fleld in which there is especial advantage to and needior a device which will permit unhindered normal fluid supply at a regulatedrate, but automatically interrupt fluid'supply' when an abnornial, higher rate of flow takes place. Y

' In a very satisfactory iorm of oil well pumping apparatusof the character mentioned, a central compressor plant provides air at relatively high pressure to a number of difi'erent pumping units and takes in the used pumping fluid from these pumping units at a lower pressure, 'while there is maintained, through suitable control means, within the piping between the. discharges of the units and the intake oi the compressor, a substantial back pressure. Each pumping unit comprises a single acting pressure-fluid-op'erated pumping motor having automatically controlled vadmission and discharge valves governed by movement of the motor piston, and the motor piston is connected to a relatively long sucker rod line and by the latter't'ofa pump plun'gerin an oil well. Because of the widely scattered'positions of-the pumps and the absence of an attendfant at each pump, it is necessary to provide automat ic control means'which will prevent serious consequences in. the event of derangement or '50 breakage. Since the motor. valves areof the a V automatic type, it isrdesirable .to'make provision ,whichwill preclude blowing of air directly through the motor cylinder from the relatively I high pressure supply line'to the considerably 55' lower pressure discharge linev should theyalv'e- My inv ntion relates. to safety.- devices, and more particularly to automatic shut-off devices pressure fluid supply plantprovides operating insureshutting down of the pump in the event of sucker rod breakage.

' It is an object of the present-invention toprovide an-improved automatic-flow-controlling device. It is another object or theinvention to provide an improved automatic shut off valve controlled by the, rate or fluid flow past it. It is a further objectfof the invention to provide an improved automatic shut of! valve for pumping 1o motors in which the .valve automatically moves toward closedposition during the period of fluid supply to a pumping motor but does not attain j closed position unless the motor operation ismaterially deranged. '.It is a still further object of the invention to provide an improved automatic shut-oi! valve for pumping motors particularly of the fluid actuated valve type. It is yet another object or the invention to-provlde an improved v motor and protective valve combination. It is astill further object of the invention to. provide an improvedcontrolling mechanism particularly adapted for use in systems of the type hereinabove mentioned for guarding against the consequences of the derangements which were referred to.

It is a" still further objector my invention to providean improved automatic 1 flow-controlling valve mechanism applicable, not only to a pump- ,ing system of the type described, but to any other use, in which periodic control of .flow is -necessary, but continuous flow is undesirable.

It is yet .a further 'object of the invention to provide animproved automatic control valve mechanism for alpumping motor adapted to permit normal operation thereof, but in the event of flow through the valve mechanism materially longer than the .tin'ie'normally' requiredfor a single working stroke'of the pump motor to shut down the pump motor entirely. Other objects and vadvantages of the invention will hereinafter 40 more fully appear.

In the accompanying drawings, in which there 1 I are shown for purposes or. illustration two forms or embodiments which my invention may assumein practice, togetherwith a detailed modification of one of themp v Fig. 1 is aview'mainly in sideelevation but with some parts broken away andother parts omitted-of a portion or a pumping apparatus in which myimproved controlling mechanism in one of its illustrative embodiments is'incorpo-. rated. a v

Fig.2 is a central section through the illustrative embodiment ofFigs. 1 m5.

Figs. 3 and 4 are vertical sections on the lines 3-3 and 4-4, respectively, of Fig. 2.

Fig. 5 is a fragmentary top view of the mechanism shown in Fig. 2.

Fig. 6 is a fragmentary view showing a modification of the species of Figs. 1 to 5.

Fig. 7 is a fragmentary view of a pumping system in which a modified embodiment of my invention is incorporated.

Fig. 8'is a central vertical section through the illustrative form of the control valve proper, shown in Fig. 7.

Referring to Figs. 1 to 5 and the mechanism therein disclosed, and particularly at first to Fig.

1, it will be noted that a pumping motor II is supported from the top member 2 of a frame I3 which is suitably supported, in a manner not shown, by a platform or,derrick floor or the like, l4. Upon the platform is also mounted an air-preheater IE, to which air undersubstantial pressure, say, of the order of 250 to 300 pounds, is supplied from a central compressor plant (not shown) through a supply line l6. The air passing through the preheater passes next through astop valve l1, and then a vent valve l8, and next an automatic controlling mechanism generally designated l9, and then through a pipe 20 to the inlet side of the pumping motor II. From the exhaust side of the pumping motor the spent air is ,returned through a pipe 2|, at a substantial back pressure, to the intake side of the compressor. The pumping motor is provided with suitable automatically controlled admission valve mechanism 22 and exhaust valve mechanism 23, and may be operated either with a certain amount of expansion or compressiomor on a substantially rectangular cycle, in accordance with the adjustments thereof. It will suflice to say with respect to this motor, that with the piston 24 thereof at the bottom of the cylinder 25, air is admitted through the admission valve mechanism and raises the piston; and that as the piston nears,

or reaches (dependent upon the adjustment) the upper end of its stroke, the admission valve mechanism 22 closes off fluid supply beneath the piston; Shortly thereafter the exhaust valve mechanism 23 releases the pressure beneath the piston 24 to the exhaust line 2|. The piston 24 is then moved downwardly by the weight of the sucker rod line 26, to which it is connected, and by the weight of the pump plunger (not shown), the rate of downward movement being retarded by the back pressure and by the quasi dash-pot action of the pump plunger. When the piston 24 approaches the bottom of its stroke, the exhaust'valve is closed; closure. of this valve taking place at the end of the stroke or somewhat before, depending upon the adjustment made in accordance with the desire to operate on the rectangular cycle or, with compression. Substantially at the bottom of the down stroke of.

the piston, the admission valve mechanism 22 again effects supply of air beneath the piston,

and the cycle is repeated. This motor makes a relatively small number of strokes a minute, 15 or 16 strokes being a not uncommon number. The motor shown is fully disclosed in Patent No. 2,004,146, granted June 11, 1935.

It will be evident. that during the upward stroke of the piston air flows in beneath the piston 24 and, assuming a relatively constant supply pressure of the air, and a relatively constant load against which the motor is operating, the rate of flow through the pipe 20 will have a relatively definite value. It will be evident, moreover, that the period of flow will be ratherdefinitely determined; in other words, it may be said that there will be periodic flows at a given rate through the pipe 20. r

Now referring to the automatic controlling mechanism, it will be observed that the mechanism |9 comprises a valve casing 3|) having a connection at 3| through which fluid is admitted thereto from the preheater l5, and. also having a connection 32 through which fluid passes to the piping 2|]. The connection 3| opens into a chamber 33, and the connection 32 opens out of a chamber 34; and these chambers are separated by a double-walled septum 35 which has a chamber or fiow passage 36 formed therein. The passage 36 is communicable with the chamber 33 through a port 31 surrounded by a valve seat 38. The chamber 36 communicates with the cham' ber 34 by a passage 39 whose lower end is surrounded by a valve seat 39. also provides a cylindrical bore 4|) in alinement The valve casing with the passage 39, and of slightly greater diameter than the passage 39. Within the bore 40 a valve element 4| is slidably mounted. This valve element has a socket or recess 42 therein, in which a valve stem 43 rests. The valve stem is loosely connected at its upper end'with a form of dash-pot mechanism which includes a perforatedv piston element 44 having passages 44 therethrough, and an intermittent sealing element 45 adapted to close passages 44 when inengagement with the member 44; the piston 44, slidably fitting in a cylindrical chamber 46 formed in the upper end of the casing 30. The

space below the valve element communicates freely with the chamber 33, as at 48.

The upper part of they valve casing 3|) contains a bore 49 whose axis is parallel to the bore of the chamber 46, and in alinement with the passage 31. Within this bore 49 a relatively heavy valve body 5|) is reciprocable. At its lower end the valve body 50 carries a valve member 5 [which is adapted to seat upon the seat 38. The valve body 50 is not a tight fit for its bore, and accordingly pressure within the chamber 36 may be transmitted to the space above the valve body. An adjustable stop member 53 limits the opening movement of the valve 5|. If it is desired/to provide a greater seating tendency'than is furnished by the mere weight of the element 5|), a spring with suitable adjusting means could obviously be arranged, for example, as shown in Fig. 6, between the top of the member 50 and the upper end of the chamber 49. A suitable cover 54 supports the adjustable stop member 53 and closes the bores 46 and 49. A suitable lower cover member 55 closes the chamber 33 at a point in contr0l1ing mechanism IS, the mode of operation can be readily understood. Flow of air through this mechanism is intermittent, as was pointed out above; for air flows through the mechanism only when the pump motor piston is on its up stroke, and the flow stops completely during the time that the piston is on its down stroke. Air entering the casing 3|) through the connection 3| has to lift the weighted valve 50, 5|, and the weight of this valve is such as to cause a small difference in pressure to exist, during the time flow through the casing 30 is taking place, between the pressure in the chamber 36 and that in the chamber 33. A difference of only one or two pounds per square inch is normally adequate.

Now assuming that the pressure is 250 pounds in the chamber 33, and, during flow to raise thepiston 24, 248 pounds in the chambers 36' and 34 and in the line 20, it will be noted that the upper surface of the valve element 4| will be, subjected to a 248-pound pressure while the lower surface is subjected to a 250 pound pressure; This small" difference in pressure tends toforce the valve 4| upwardly towards its seat at the lower end of they passage 39, being more than adequate to. lift the Weight of parts 4|, 43,44 and 45.

valve 4| can reach the upper end of its travel and seat.

When the up-stroke of the pump motor piston- 24 is :completed, flow of airthrough the valve stops, and the pressure on both sides of valves and 4| will equalize, by reason of the fact that valve 4| is not a tight fit for its chamber or bore 4|]. With the pressure equal on both sides of the. valve 4 I, the latter willfldrop to its bottomposition; The dash-pot piston 44 might tend to be retarded in its downward movement, but this is pre vented by reason of the fact that as soon as the valve 4| drops away from contact with the stem' 43, the latter isfree to move downwardly and lower the sealing member45 relative to the piston 44; and thereupon flow through the ports in the piston 44 will permit free downward movement of the dash-pot piston 44. By'the time the down stroke of the piston 24 has been completed, the

. parts are again. in the position shown in Fig. 2,

and ready again to go through the cycle which a has been described.-

The cycle explained occurswith each stroke of the pump. Should the flow of air through the motor become constant at any time-as through sticking of the distribution valves in open position, -or any other derang'ementthe' valve 4| would continue its upward movement until it seated, due to'a difference in pressure caused by, a continuous flow;of suchduration as.

to permit the valve 4| to completeits upward travel. When onceclosed, the valve 4| will remain closed-until-reopened intentionally, which may be done by closing the throttle I"! and opening the vent l8.

Should the suck r rods break, allowing the pump piston 24 to;speed upon the up stroke,

there wouldbe an increased rapidity of the flow ofair' past the valve 5|, which, due to the throttling. occasioned by the limited opening of this valve when rapid flow is occurring, would cause a greater difierence between. the pressures in chambers 33 and 36. Thisadditional pressure difference would be suiflcient to increase the speed of movement of thevalve 4| substantially'and' cause'it to close and shut off the .air to the pump.

It will be understoodthat the additional pressure drop will be quite substantial, sincethe. ad-

justing screw 53 will be set to permit only the desired rate of flow for normal pumping operation, to occur through the port 31, without substantial' throttling efiect. A bypass, 56 is provided, and this may, when it is desired to run the pumpfaster than its normal speed, for a short time, be made operative by opening a valve $1 to permit flow past thef mechanism l9 ate more rapid rate than would be possible without closing the valve 4|. I

From the foregoing description it will be ev'ident that I have provided" an improved valve mechanism which is in some measure a governor valve, since any tendency to overspeed would be Upward move-' ment of the valve 4| is retarded by the piston 44 to suchan-extent that the normal up-stroke'of the pump piston 24 will be completed before the control or shut-oi! valve mechanism 65.

' during either valve 50, 5| controls the maximum flow rate. Thisniechanism as a whole is, however, of primaryimportance in that it prevents waste of air in the-event of -derangement of the, pump mechachecked by closing of the valve 4 Moreover, the

-nism,.and'in that it shuts down the pump and prevents serious damagein the eventthat any breakage of the sucker rod line or blowing through of pump packings takes place.

The use of the valve mechanism, including the valve 50, 5|, may be dispensed with, if this be desired, and in the species of the invention, from certainof its aspects, shown in Figs, '7 and 8, the weighted valve and its function are omitted. It'will benoted that, as in the firstform, a suitable platform Gl supports a frame 62, from whose top 63 a-pressure fluid operated pumping motor 64 is suspended. The motor has a'fluid controlled admission valve mechanism 65 and a fluid controlledexhaust valve mechanism 65, and its piston rod 61 is connected with-a polished rod 68 of an oil \ivell pump mechanism whose discharge line 69 is arranged somewhat abovetheconnection 10 for. easing head gases. A central com pressor plant, not shown, which may supply air at several hundred pounds pressure to a number of different pumping motors is here also the usual source of fluid supply. The supply line 1| conducts air from such a source athigh-press'ure .to a preheaterll'and from the latter a line 13 conducts the heated high-pressure live fluid past a stop valve I4, bleed valve 15, and an automatic valve 16, to the admission 'Fluid'is exhausted from the motor 64 through the exhaust valve mechanism 66 .ata substantial back pressure and'returned to the intake .of the central compressor through an exhaust fluid line -A by-pass 18 having a suitable controlling valve I9 is arranged -to' per.-

mit fluid to flow from the line I3 to the admission valve mechanism 65 without passing. through the automatic control valve 16 whenever this may be.

presence of a third stop valve 80, it is possible to disconnect the automatic stop valve 15 completely and still operate the pump, while repairsor' adjustments are. made or while cleaning the-autoniatic stop'valve.

. The valve mechanism 16 is adapted to permit the normal flow of air to the pump motor 64 with- This means that the valve out impediment. I ineifective' to-interrupt fluid mechanism I6 is flow past it when such flow occurs 'ata con-- stant rate'during. the pumping strokes of. the motor andfor the periods-during which such possible so that rushesofair as the admission valve opens, and

case, the valve mechanism-Will operate upon a sustained rush of a'irat, anfei'zcessive' rate co'mpletely to interrupt fluid supply past it'.

' The valve mechanism '16 comprises a casing desirable for ashort time. By reason of the 70 I v and suitable. valve-and control devices within the casing for effecting the mode of operation mentioned. The casing is of composite construction, and includes a main body member having a v septum 82 dividing the interior thereof intoan admission space 83 and a discharge space 84. The septumis ported at 85.- The other portion of the casing includes a member 86 having a depending ported cylindrical sleeve member 81 provided with packing means 88 adapted to form aseal with the wall of the port 85, said sleeve having a series of openings 89 to conduct fluid entering its interior from the, admission chamber 83, into the discharge chamber 84. The depending sleeve 81 is supported upon a flange 98 which is adapted to be held by suitable screws 9| to the upper portion of the casing member The casing member 86 supports, at its upper end, a cylinder portion 92 having a bore 93 and a head 94. The bore 93 slidably receives a dash-pot piston 95, and a by-pass passage 96 controlled by an adjustable throttling-screw 91, accessible by removal of a threaded plug 98, controls the by-passing of fluid from top to bottom of the dash-pot cylinder 92. Within the admission space there is mounted a sleeve I88 having a ported bottom portion I8I suitably connected at I82 to an adjusting screw I83. This sleeve I88 may be adjusted to a top-most position with its upper end in contact with thelower end of the sleeve portion 81. Under such circumstances, flow from the valve mechanism would obviously move the sleeve I88 downwardly, a variable flow space may be provided between the top of the sleeve I88 and the bottom of the sleeve( 81, and a differential in'pressure between the space at the top of the former and the space at the bottom of the same may be produced. A desirable adjustment provides a difference in pressure of perhaps one-half pound per square inch. Within the sleeve I88, which provides a cylindrical bore I85 a piston I86 is slidablymounted. This. piston is connected toa rod I81 which extends upwardly to a valve element I88 which. cooperates with a valve seat I89 formed on the lower end of the dash-pot piston 95. Upward movement of the rod I81causes the valve element I88 to push the dash-pot piston upwardly. The

dash-pot piston is traversed by a plurality of pas-" seat I89 for the valve I88, so that upon separation of the valve I 88from its seat I89, flow may lying between the flange 98 and the bottom of the cylinder portion 92 is provided with a glassed inspection-port II 5, and by observing the positions of the single ring I I6 and of the double ring H1 and of the double-width ring II8 the position of the valve may be noted and proper adjustments readily determined. Piston I86 coacts with 81 as a valve;

When it is desired that the valve mechanism 16 shall not" operate with any tendency to shut; off flow through the valve casing 8|, except upon a prolonged abnormal rush of fluid through the latter, adjustmentscan be made as by providing a relatively larger space between the top of the sleeve I88 and the bottom of the sleeve 81; and by obstructing, through the throttling screw 91, flow through the by-pass 96, moreover, there will be no or very little movement of the valve member I86 toward the lower end of the sleeve 81,.during the normal flow of the fluid to the pumping motor which occurs during the admispumping motor.

sion periods of the latter. If desired, however, by somewhat restricting the flow area between the top of the sleeve I88 and the bottom of the sleeve 81, and by increasing to the necessary amount the freedom of flow through the-.by-pass passage 96, the valve I86 may be caused to move from its bottom position towards closed position,

the more complex situation, that an adjustment is made which causes the valve member I86 to move upwardly during each period-of admission to the pumping motor, it will be observed that the valve element will be subjected during fluid flow to a greater pressure at its bottom through the passages I8I than actsupon its upper end. Upon the opening of the admission valve a rush oi air will occur and the valve I86 will gradually begin to move upward, but its upward rate of movement will be retarded by the dash-pot 96, and it will not attain top-most position before cut-oil occurs. It will be immediately released, from its upward moving tendency, upon equalization of the pressure at opposite sides of the be impossible. By adjusting the screw I83 to valve mechanism 16, which occurs upon closing of the admission valve mechanism 65. The valve I88 will then fall away from the seat I89 and the valve I86 will drop immediately to its bottom-most position. The dash-pot piston 95 will promptly drop down also until it again engages the valve element I88, this being made possible by the openings II8 through the piston H5; and

the parts" will be ready for a new cycle.

- From the description given, the mode of operation with other adjustments will be apparent, and it will be evident that I have provided imflow, and even permissible supernormal flows of brief duration, but which will close off pressure flow with certainty upon protracted exces'siveflow. It will be evident that this device also is simple, rugged, not easily deranged, adjustable to difierent desired conditions of operation, and thoroughly efiective in operation. It will further be noted that the adjustment need not be altered during the cleaning of the device, for'by removing the screws 9| the seat for the valve I86 which exists at the bottom of the sleeve 81 may be readily cleaned, and the upper portions of the device overhauled as may be desired without any interference with the adjustment of the valve mechanism per se. The dash-pot cylinder is placed so high as to eliminate to a large extent likelihood of access thereto of dirt or oil in the air flowing through the valve mechanism. When it is necessary to clean the apparatus, the

'by-pass previously described may be used to prevent the necessity for shutting down the pump. I

While I have in this application specifically describedtwo forms and a minor modification atom of them, which my invention in various aspects may assume in practice,it will be understood thatthese forms of the same are shown for purposes of illustration and that the invention may be further modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

This application is a continuation in part of my copending applications Serial No. 681,542, filed July 21, 1933 (now abanddifed) and Serial Assuming, as that is "'aioa'oea. I v v specti velm-a weighted valve associated with one No."l46,l'll, filed'Sept. 29,1934, and also of my ducing a V A opposite sides oi! said valve during flow through said casing, and means governed by such difler- .earlier application Serial No. 619,658, filed June ential in pressure and associated withthe other of said valves whereby the same is caused to close after a predetermined period "of uniform flow past the first mentioned valve.

2. In' a valve mechamsm, a casing providing a passage, a plurality of valves insaidcasing each adapted to interrupt flow. through said. pamage, means associated with one of said valves for pro ducing a difierential in pressure betweenthe spectively, a weighted valve associated with one ,ofsaid valv'e seats,- a 'valve responsive to presopposite sides of said valve during flow through said casing, and means associated withthe other of said valves for subjecting the same throughoutfiow through said casing to an uncounterbal- 'anced closing force which is a function of the difierential in pressure existing between the opposite sides of the first mentioned valve.

-3. In a valveme'chanism, in combination, a

casing, parallel bores therein, valve seats coaxial with saidbores, said casing having therein a supply passage, leading-to oneof said-seats, a

passage leading from the other side of said seat to the other seat, and a delivery passage leading from the other side of said last mentioned seat,

a weighted valve associated with the'firstmen 'tioned one of said seats, and a valveresponsive to the pressures in and having surfaces commujpleating directly with the supply. passage and the second mentioned passage ifor controlling flow past the second mentioned valve seat of fluid passing through said second mentioned passage. 4. In a valve mechanism, in combination, a casing, parallel bores therein, valve seats coaxial with said bores,'fiow passages leadingto one of said valve "seats, connecting" said valve seats, and v leading from the'otherof saidvalve seats, re-' spectively, a weighted valve associated with one of said valve seats, and an imperforate valve directly "responsive to and movable by the differential in pressure between the supply passage and the space beyond the first mentioned valve for controlling flow past-the second valve seat.

'5. In a valve mechanism, in combination, a casing, parallel bores therein, valve seats coaxial with said bores, flow passages leading to oneoi' said valve seats, connecting said valve seats, and leading fromtheother of-said valve seats, re-l sure in the supply passage and'inthe' space'be v yond the first mentioned' valve for controlling new past the'secondvalve seat, said second mentioned valve 'havingj av wide range of .movement .1

- without affecting fiow'tlirough said pasing, and;

dashpot means associated with said second mentioned valve for controlling the movement thereof. 1

J 6. In a valve-mechanism, in combination, a]. casing, parallel boresthereimvalve seats coaxial with'said bores, flow passages 'leading to. one 01- said valve seats, connecting said valve seats, and

leading from the other of said valve seats,.re-

' of said valve seats, a valve responsive to pressure in the supply passage and inv the space'beyondthe first mentioned valve for controlling .flow

past the second valve seat, said second mentioned valve having a wide range. of movement without affecting fiow through said casing, and dashpot means associated with said second mentioned valve forcontrolling the movement thereof, said dashpot means providing a uniform opposition to valve movement in a closing direction.

7. In combination, an expansible chamber motor, a load movable by said motor, and means for controlling the supply of motive, fluid to said motor comprising means for regulating therate of fluid supply to said motorto preclude excessive speed thereof during normal loaded operation including 'a vaive for eflecting difierent reduc tions -in"pressure in accordance with different rates of flow, and-separate valve means controlled 1 by such reductions in pressure and varying in operating speed in accordance therewith and;

moving substantially uniformly during any given reduction throughout the continuance thereof for automatically interrupting flow of fluid to said motor in .the event said motor loses its load.

8. In combination, a motor including a cylinder having a piston, movable therein, a load connected with said piston, fluid distribution means, and fluid supply means having controlling mechanism associated therewith including a valve device for limiting fluid supply to said motor to a rate adapted to'the degired rate of loaded piston movement with a pre etermined small drop in pressure-below supply pressure, and means controlled by the drop in pressure beyond said valve device for-automatically interruptingpressure supply to the piston and shutting down the motor until same is operator-restarted in the event of substantial exceeding of said rate of piston movement.

9. In a valve mechanism, in combination, a casing having a passage extending therethrough and traversing aplurality of valve seats, a valve arranged to cooperate with the valve seat first reached by fluid passing through said passage and having associated therewith means forproducing- I a-differential in pressure between opposite sides of said seat, and a second valve subjected on the opposite endsdirectly to and responsive to the pressures atopp'osite sides of the first valve seat for controlling flow past the second-valve seat andbiased towards closed position by the diflerences in such pressures. v,

10-. In a valve mechanism, in combination, a casinglhaving a passage extendingv therethrough and traversing a plurality of -valve seats, a valve arranged to cooperate with the, valve seat first reached by fluid passing through said passage and having associated therewith meansfor producing a, differential in pressure between opposite sides of said seat, a second valve responsive to the pressures for controlling flow past and having a substantial range of movement before afiecting flow, and means associated with the at opposite sides of the first valve seat- I the second valve seat second mentioned valve for controlling the mo'vement thereof and providing substantially uniform said valve. l V '11. In a2 valve mechanism, in combination, a, casing having a passage extending therethrough and traversing a plurality or valve seats, a valve arranged to cooperate withthe'valve seat first reached by fluidlpassing through said passage and regulation ,thereot irrespective of movement-of and having a substantial range of movement before affecting such fiow, and means associated with the second mentioned valve for controlling the movement thereof in a closing direction only and providing a substantially uniform resistance to closing movc'nent throughout valve movement.

12. In a valve mechanism, in combination, a casing having a passage extending therethrough and traversing a plurality of valve seats, a valve arranged to cooperate with the valve seat first reached by fluid passing through said passage and having associated therewith means for producing a differential in pressurebetween opposite sides of said seat, an imperforate second valve responsive to and movable by the differential between a the pressures at opposite sides of the first valve seat for controlling flow past the second valve seat, and retarding means associated with the second mentioned valve for controlling the movement thereof in a closing direction only.

13. In a valve mechanism, in combination, a casing having a passage extending therethrough and traversing a plurality of valve seats, a valve arranged to cooperate with the valve seat first reached by fluid passing through said passage and having associated therewith means for producing .a difierential in pressure between opposite sides of said seat, a second valve responsive to the pressures at opposite sides of the first valve seat and movable to control flow past the second valve seat, and dash-pot means associated with the second mentioned valve for retarding but not interrupting movement thereof.

14. In a valve mechanism, in combination, a casing having a passage extending therethrough and traversing a plurality of valve seats, a valve arranged to cooperate with the valve seat first reached by fluid passing through said passage and having associated therewith means for producing a differential in pressure between opposite sides of said seat, an imperforate second valve responsive to the pressures at opposite sides of the first valve seat for controlling flow pastthe second valve seat, and dash-pot meansv associated with the second mentioned valve for controlling the movement thereof.

15. In a valve mechanism, in combination, a casing having a passage extending therethrough and traversing a plurality of valve seats, a valve arranged to cooperate with the valve seat first reached by fluid passing through said passage and having associatedtherewith means for producing a differential in pressure between opposite sides of said seat, a second valve responsive to the pressures at opposite sides of the first valve seat for controlling flow past the second valve. seat, and dash-pot means associated with the second mentioned valve for controlling the movement thereof in a closing direction only.

16. In a valve mechanism, in combination, a casing" having a passage extending therethrough and traversing a plurality of valve seats. a valve arranged to cooperate with the valve seat first reached by fluid passing though said passage and having associated therewith means for producing a differential in pressure between opposite sides of said seat, a second valve responsive to the pressures at opposite sides of the first valve seat for controlling flow past the second valve seat, and dash-pot means associated with the pressure fluid movable element, a load movable by said element, and means for controlling the supply of motive fluid to said motor comprising means for regulating the rate of fluid supply to said motor to preclude excessive speed thereof during normal loaded operation, and pressure fluid operated means controlled by pressure conditions beyond said regulating means and having a substantially uniform rate of closing movement during normal load movement by said motor for automatically interrupting flow of fluid to said motor in the event said motor loses its load.

18. In combination, a motor comprising admission and exhaust valve mechanisms, a load movable by said motor, and means for controlling the supply of motive fluid to said motor comprising weighted valve means for regulating the rate of fluid supply to said motor to preclude excessive speed thereof during normal loaded operation, and pressure fluid operated means controlled by pressure conditions beyond said weighted valve means and having a substantially uniform rate of closing movement during normal load movement by said motor for automatically interrupting flow of fluid to said motor in the event said motor loses its load.

19. In combination, in a valve mechanism, a casing providing a valve seat, a valve movable towards said seat, means for subjecting the opposite sides of said valve to a differential pressure during flow through said casing whereby said valve approaches said seat at a substantially uniform rate while flow through said casing occurs at a uniform rate, and means for resisting the movement of said valve towards its seat operative to permit substantially unimpeded movement of said valve in the opposite direction.

20. In combination, a motor including a cylinder, distributing valve mechanism, a piston, and fluid supply and exhaust means for said motor, and means for automatically controlling fluid supply to said motor including a valve device automatically moved in a direction tointerrupt fluid supply to said motor during and throughout each admission of fluid to said motor, and means for controlling the rate of movement of said valve to preclude interruption of fluid supply during normal motor operation.

'fiuidsupply to said motor including, a valve device automatically moved in a direction to interrupt fluid supply to said motor during a large part of each admission of fluid to said motor and having a quick return movement during motor exhausting, and means for controlling the rate of movement of said valve to preclude interruption of fluid supply during normal motor operation.

22 In combination, -a motor comprising a cylinder having a piston reciprocable therein, and means for supplying operating fluid to said motor at a controlled rate including a supply line having a controlling valve therein governed by the rate of fluid flow to said motor and mov- 50 .automatic means associated therewith for re-v .-a,1oa,9ca f ing towards closed positionduring each admis sion of fluid to said motor but constrained during normal motor operation to a rate of move- ,ment precluding complete closing prior to completion ofadmission to said motor;

23. In combination, a motor comprising a cylinderhaving a piston reciprocable therein, and means for supplying operating fluid to said motor at a controlled rate including asupply line having a controlling valve therein, means for imparting to said valve automatically during work- .ing piston movement a force tending'to close the valve andefi'ective to. produce valve move- .ment in a closing direction, and means for -con' trolling movement of said valve by such force precluding during normal motor operation complete closing of said valvei-prior to'completion the motor performs a workingcycle, said valve cycle including a movement in a closing direction during each working stroke of the motor and a movement in an opening direction intermediate successive working strokes of the motor, said valve having automatic means associated therewith for retarding the movement whereby it traverses the first portion of its cycle more slowly take place.

' completion of the working'stroke of said motor,

than the 'motor traverses the corresponding'porf disposed, in the absence of flow between said tion of its cycle, whereby closing of said valve prior to the completion of the working stroke of said motor, during normal operation, does not 25. In. combination, a motor comprising a cylinder having apiston reciprocable therein, and controlling means for said motor including a valve for controlling the supply of working fluid to'said motonand means controlled during the working stroke of the piston by the rate of piston movement for causing said valve to pass through a cycle of movement each time the motor performs a working cycle, said valve cycle including a movement in a closing direction-during each working stroke of the motor and a movement in an opening direction intermediate successive working strokes of the motor, said valve having tarding its movements wherebyit traverses the first portion of its cycle more slowly than the motor traverses the correspondingportion of its cycle, whereby closing of said valve prior to the during normal operation, doesnot take place.

26, In combination,'a motor comprising a cylinjder having a. piston reciprocable therein, and

controlling means for said motor including a valve for controlling the supply of working fluid to said motor, and means governedduringthe working piston stroke by the fluid passing to said motor for causing said valve to pass through a cycle of movement each time the motor performs a working cycle, said valve cycle including a movement in a closing direction during each working stroke of the motor and a movement in an open- I ing direction intermediate successive working I movements whereby it traverses the first portion strokes of the motor, said valve having automatic means associated therewith for retarding its of its cycle more slowly than the motor traverses the corresponding portion of its cycle, whereby closing of said valve prior to the completion of 7 the working stroke of said motor, during normal operation, does not take place.

27. In combination, avalve casing having supmeans for creating a diiferential pressure varying directly with the rate of 110W from said discharge chamber and subjecting said valve thereto in a closing direction, said differential pressure adapted to impart slow movement in a closing direction to said valve even during the normal intended flow between said chambers, and

normal intended flow between said chambers,

and pressure fluid means for preventing closure ofrsaid valve upon but momentary increases in such differential pressure.

29. In combination, a valve casing having supply and discharge chambers, a valve for controlling communication between said chambers chambers, in full-open position and having a substantial range of movement in a closing direction before affecting freedom of flow between said chambers, means for creating a differential pres sure varying directly with therate of flow from said discharge chamber and subjecting said valve thereto in a closing direction, said differential pressure adapted to impart slow-movement in a closing directionto said valve even during the normal intended flow between said chambers, and

' means cooperating with said valve to' preclude closure thereof during the-first occurrence of an abnormal pressure drop in said discharge chamber and operative to permit substantially unre-- tarded valve movement towards open position/ from a partially closed position.

30. In combination, a valve casing having sup-- ply and discharge chambers a valve for controlling communication between said chambers,

1 ply and discharge chambers, a valve for controlling communication between said chambers,

means for creating a difierential pressure varying directly with the rate of fiow'from said discharge chamber and subjecting said valve thereto in a closing direction, said differential pressure adapted to impart/slow movement in a closing direction to said valve even during the normal intended flow betweensaid chambers, and means including a one-way fluid dash-pot-cooperating with said valve to preclude closure thereof during the first occurrence of an abnormal press drop in said discharge chamber.

I 31. In combination, a valve casing having supply and discharge chambers, a valve for controlling communication between said chambers and free to move from open to closed position and having substantial movement in a closing direction during which itleaves communication between said chambers unaffected, means for subiecting said valve to a closing force upon 'an-abnormal increase in flow from said discharge chamber, and unidirectionally acting fluid means for limiting the rate of valve movement during'75 ing a continuously open communication with thesupply chamber for subjecting said valve to a closing force upon an abnormal increase in flow from said discharge chamber, and means arranged to oppose the movement of said valve by the pressure variations efiected'upon flow variation, for limiting the rate of valve closure and precluding said closing force from afiecting communication between said chambers during the initial period of increased flow but permitting valve closure upon sustained increased flow.

33. In combination, a valve casing having supply and'discharge chambers, a port connecting said chambers and surrounded by a valve seat, a valve arranged to cooperate with said seat, a piston having a one-way attachment to said valve, means forsubjecting opposite sides of said piston to pressure conditions in said discharge chamber delaying the communicationof variations in pressure to one side of the piston, and means including a continuously open communication with the supply chamber for subjecting said valve to a differential closing pressure.

34. In combination, a valve casing having supply and discharge chambers, a port connecting said chambers and surrounded by a valve seat, a valve arranged to cooperate with said seat, and

means for maintaining said valve open during, brief variations in pressure between said cham bers but operative to permit movement thereof gradually towards clpsed position and efiective automatically to effect closure of said valve upon substantial continued drop in pressure in said discharge chamber including a piston attached to said valve, means for subjecting opposite sides of saidpiston to pressure conditions in said discharge chamber delaying the communication of variations in pressure to one side of the piston,

and means for subjecting said valve to a differential closing pressure including a continuously open communication with the supply chamber and means for shielding said valve from the direct rush of fluid through said port.

35. In combination, a valve casing having sup- ,ply and discharge spaces separated by a ported wall, a valve" arranged in the supply space for cooperation with the port'in said wall, and means for eifecting automatic closure of said valve upon a sustained substantial reduction in pressure in said discharge space but precluding'instantaneous closure of said valve though permitting immediate movement thereof upon the occurrence of a substantial reduction in such pressure including a cylinder formed in said valve casing and alined with the port in said wall, a, valve-connected piston in said cylinder, and means forconnecting one end of said cylinder directly with the discharge space and providing for the other end,

aioacez for efifect'ing automatic closure of said valve upon a sustained substantial reduction in pressure in said discharge space but precluding instantaneous closure of said val e upon the occurrence of a substantial reduct on in such pressure includinga sleeve open at both ends and surrounding said valve, a piston connected with said valve, a cylinder at the discharge side of the ported wall and receiving said piston, and means for connecting one end of said cylinder directly with the discharge space and providing for the other end thereof an adjustably restricted connection with the dischargespace.

37. In combination, -a valve casing having supply and discharge spaces separated by a ported wall, a valve arranged in the supply space for cooperation with the port in saidwall, and means for eiiecting automatic closure of said valve upon a sustained substantial reduction in pressure in said discharge space but precluding instantaneous closure of said valve upon the occurrence of a substantial reduction in such pressure, including means for shielding said valve from direct action of the flowing fluid while subjecting it at all times during flow therethrough to supply-side pressure in a closing direction and to the pressure at the port in said vwall in the opposite direction, and means at the discharge side of the ported seat for maintaining said valve open during normal pressure differences between said supply and discharge spaces and during momentary increases of such difierences but operative to permit closure on substantial occurrences of such increased pressure differences.

38. In combination, a line constantly supplied with pressure fluid, a line for conducting fluid from. said first mentioned line, automatic means for connecting said lines normally operative to establish repeated connections for relatively short periods with intermediate flow interruptions, and a valve mechanism also controlling flow between said lines and including a valve for closing communication between said lines, means associated with said valve for moving the same when normal flow between said lines is taking place in a closing direction, and regulating means for the closing movement of said valve efiective to limit its rate of movement so that closing thereof during normal 'fiow periods is precluded though said valve moves in a closing direction, but ineffective to prevent closure of said valve on occurrence of abnormally protracted flow.

39. In combination, a line const ntly supplied with pressure fluid, a line for co ducting fluid from said first mentioned line. aut matic means for connecting said lines normally operative to establish repeated connections for relatively short periods with intermediate flow interruptions, and a valve mechanism also controlling flow between said lines and including a. valve for closing communication between said lines, means associated with said valve for moving the same when normal flow between said lines is taking place in a closing direction, and regulating means for the closing movement of said valve'efiective to limit its'rate of movement so that closing thereof during normal flow periods is precluded though said valve moves in a closing direction, but inefiective to prevent closure of said valve on occurrence of abnormally high flow.

40. In combination, a valve casing having supply and discharge spaces separated by'a ported wall, a valve arranged in the supply space for cooperation withthe port in said wall, a sleeve in the supply space having a bore of uniform cross 40 controlling means and structurally distinct, relainterrupting communication between said cylinsection for receiving said valve and. open at its top and surrounding the valve and permittin continuous access of supply space pressure to the ments of said valve.

surface of said valve remote-from the port, and,

means for yieldingly retarding closing move- '41. In combination; a valve casing having supply and discharge spaces separated by a ported wall, avalve arranged in the supply space for cooperation with the port in said wall, a sleeve in the supply space open at its top and surrounding the valve and providing a stationary guide for the latter and permitting continuous access of supply space pressure to the surface of said valve remote from the 'port,and a fluid dashpot for retarding valve movements.

wall, a valve arranged in the supply space for cooperation with the port in. said wall, a sleeve in the supply space open at its top and surrounding the valve and providing a stationary guide for the latter and permitting continuous access of supply space pressure to the surface of said valve remote from the port, and a dashpot at the discharge side of said port for retarding valve movements only in a closing direction.

43. In combination, a valve casing-having supply and discharge spaces separated by 'a ported wall, a valve arranged in the supply space forfcooperation with the. port in said wall, an axially adjustable sleeve in the supply space open at its top and surroundingthe valve and permittingaccess of pressure tothe surface of said valve remote from the port, and means for. yieldingly retarding closing movements of said valve.

44. In combination, a source of operating fluid, a fluid motor having a cylinder and fluid distributing means for said cylinder for controlling motive fluid supply and exhaust including exhaust tively movable, valve means. controlling admission and cut off, said valve means'having actuating means for causing the same to eflect admission of fluid from said source and after an interval to cut off the admission of fluid from said source, and controlling valve means for interrupting communication between said cylinder and said source in the eventsaid first mentioned valve means fails to effect cut-off.within a predetermined time after admissionoccurs and ex-.

= haust and admission become concurrent.

45. In combination, a source of operating-fluid,

a. fluid motor having acylinder and-fluid-disan-interval to out off the admission of fluid from said source, and controlling valve means for interrupting communication between said cylinder and said source in the event said first mentioned valve means fails to effect cut-off within a pre- "determined time after admission occurs, said last mentioned valve means including a valve element Y having operating means moving it in a closing =direction during each period of admission.

46. In combination, a source of operating fluid, a fluid motor having a cylinder and fluid distributln'g means for said cylinder including valve I means controlling admission and cut off and having actuating means for causing-thesame to ef- .fect' admission offluid from said source and after an. interval to cut off theadmission of fluid from said source, and controlling valve. means for of movement in a closing direction and throttling flow only after a substantial portion of such range has been completed and having operating means der and said source in the event said first mentioned valve means fails to effect cut-ofi within a predetermined time after admission occurs, said last mentioned valve means including a valve ele- 5 ment having operating means moving it towards closed position during each period of admission but at a rateless than suflicient'to effect closure during a normal period of admission to said motor.

47. In combination, a source of operating fluid, a fluid motorhaving a cylinder and fluid distributing means for said cylinder including valve means controlling admission and cut on and having actuating means for causing the same to effect admission of fluid from said source and after an interval to out 01f thev admission of fluid from said source, and controlling valve means for interrupting communication between said cylinder and said source in the event saidflrst mentioned valve means fails to effect cut-oi). within a predetermined time after admission occurs, said last mentionedvalve means including a valve element having a relatively long range for moving it in a closing direction during each period of admission. I

In combination, a valve casing having supply and discharge chambers, a valve for control ling communication between said chambers, said valve in the absence of flow between said chambers normally in aposition in which it'is without effect on rate of flow and. having -a substantial -movement in a closing direction before afiecting materially'the rate of flow from said discharge. chamber, means for creating a differential pres-" sure varying-directly with the rate of flow from said discharge chamber and subjecting said valve thereto in a closingfdirection, said difierential pressure adapted to impart slow movement in a closing direction to said valve even during the normal intended'flow between said chambers, and pressure fluid means for preventing closure of said valve upon but momentary increases in such diirerential pressure. i

v 49. In combination, a valve casing having supply and discharge chambers, passage means con-. necting said chambers, a valve movable to in .50 terrupt' communication between said chambers, means for supporting said valve, when there isv no flow between said chambers, in a position in which said passage-means is completely unobstructed by said valve-and from which position said valve has a substantial travel in a closing w direction before commencing to obstruct said passage means, means for. creating a diflerential pressure varying with; the rate of flow through said passagemeans and subjecting said valve thereto in a closing direction, and means for opposing a resistance to the closing movement of said valve varying with the rate of closing movement, said differential pressure during periods of normal flow between said chambers'sumcient to overcome the resistance opposed at a relatively low speed of valve movement by said means for opposing closing movement of 'said valve, whereby said valve moves at a slow rate and for a substantial period in flow-obstruoting'direction, be-

fore obstructing said passage-means, upon the initiation of normal flow between'said chambers.

' 50. A system ofthe class wherein; a source of motive fluid is recurrently connected through a valve mechanism with a pressure fluid motor cylinder for periods corresponding to the normal periods of admission to said motor and in which the motor is normally under a load adapted to preclude wide fluctuations in the rate of motive fluid supply thereto and in which valve devices are provided for cutting off motive fluid supply to the motor in the event of loss of the motor load, characterized by the fact that said valve devices include a valve movable to a position to cut oil motive fluid supply to the motor and having associated therewith means for creating a pressure diflerential during such periods or connection, means for subjecting said valve thereto,

and means for opposing the effect thereof on said 

